This invention relates to apparatus for sorting, conveying and distributing items, and in particular to a sorting, conveying and distributing system for the handling of rigid or flexible packages of documents, or loosely packaged documents, and for allowing the positioning, distribution and accumulation of these packages for subsequent handling.
In recent years, the overnight courier and package delivery industry has grown to the point where the companies have a relatively short period of time to collect, sort and deliver hundreds of thousands of packages in order to meet the promised next day delivery deadline.
The industry quickly outgrew the capacity of manual sortation systems and attempted to adapt known sortation-conveyor systems to solve the enormous sorting and conveying work load. The prior art sorting and conveying systems comprised divided, multi-laned conveyors having separate belts and dividers which conveyed the packages to chutes that had to be configured to meet the needs of the conveyor system. The prior art apparatus was found to be inefficient and noneconomical with respect to an optimum layout for the use of man power and space. One specific complaint against adaptation of the prior art apparatus to the overnight package delivery industry was that the layout of the sorting-conveying apparatus was dictated by the equipment which required excessive space to accomplish the sortation-conveying process. Moreover, in order to prevent jamming of loosely packaged or flexible packages of documents, the prior art apparatus required multiple belt, complicated mechanical conveying systems which were uneconomical and inefficient with respect to the use of space, man power and cost. Another problem with the prior art systems was that they did not allow for the placing of the discharge and collection points in the best positions for the utilization of man power and space. See for example U.S. Patent Nos. 4,047,712; 3,032,211: 2,833,393; and 2,679,309 for prior art sorting-conveying systems having features which were adapted for use in the overnight package delivery industry with limited success.
Another problem resulting from the use of prior art sorting-conveying systems relates to the particular type of material used by numerous courier service companies to make their envelopes. The material is spun bonded olefin which is very strong and durable, but which becomes flimsy, pliable and dogeared with repeated handling whereby the envelope develops numerous edges or corners which are susceptible to catching on protrusions or in cracks while being conveyed. The prior art systems have numerous places and cracks where the edges and corners of such packages may catch and cause a jam. For example, the space between the lane dividers and the conveyor belts immediately below were a continuous source of jams and stoppages in the prior art systems. Also, the prior art systems were not designed to eliminate such cracks and other potential problem points where jams and stoppages could occur in the system between the conveyor belt and the collection point. The prior art systems had no convenient means for clearing a jam which occurred at points in the system past the conveyor surfaces.
Therefore, a need has developed for a sorting, conveying, and distributing system for the handling of packages which are susceptible to snagging on the conveyor surface and causing jams, or which are susceptible to failure whereby the contents will be spilled and cause a jam.